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    <title>rref</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>rref</b> -  computes  matrix row echelon form by lu transformations</p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>R=rref(A)  </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>A</b>
        </tt>:  m x n matrix with scalar entries</li>
      <li>
        <tt>
          <b>R</b>
        </tt>:  m x n matrix,row echelon form of a</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>rref</b>
      </tt> computes the row echelon form of the given matrix by left lu
    decomposition. If ones need the transformation used just call
    <tt>
        <b>X=rref([A,eye(m,m)])</b>
      </tt> the row echelon form <tt>
        <b>R</b>
      </tt> is <tt>
        <b>X(:,1:n)</b>
      </tt> and
    the left transformation <tt>
        <b>L</b>
      </tt> is given by <tt>
        <b>X(:,n+1:n+m)</b>
      </tt> such as <tt>
        <b>L*A=R</b>
      </tt>
    </p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

A=[1 2;3 4;5 6];
X=rref([A,eye(3,3)]);
R=X(:,1:2)
L=X(:,3:5);L*A
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="lu.htm">
        <tt>
          <b>lu</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="qr.htm">
        <tt>
          <b>qr</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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